Baylen Bay, the fictional setting of Ice Cream Man, looks to be the dictionary definition of “idyllic.” Since the movie is directed by Eli Roth (Thanksgiving), you know that’s pure facade. Like, one block over, perhaps a young Kyle MacLachlan is stumbling upon an ant-laden ear in the grass.

On Roth’s block, however, the suburb’s children are all abuzz over the new dispenser of frozen desserts (Ari Millen, TV’s Orphan Black), whose truck blasts a Silver Shamrock-esque earworm of a jingle. Once kids eat his treats, they’re susceptible to an act of Weapons-style witchery hearing that tune unlocks: mass parricide.

Thanks to his lactose intolerance, our preteen protagonist (Charlie Zeltzer, a real find) is spared. He spends the last two-thirds of the movie under siege in school — shades of 2014’s Cooties — as his classmates prey upon anyone not following the Pied Piper of Popsicles. (“Is this some kind of Zombie Pajama Day Challenge?” asks one confused faculty member.)

This is Ice Cream Man’s demarcation point, as Roth, unshackled from an MPA rating, goes whole-hog on the gore — so soupy, so chunky — that you’re either in or long gone. I’d be the latter, if not for Roth and co-writer Noah Belson stirring in an equal amount of gallows humor. Sight gags get increasingly ghoulish, like a stairwell sight of two kids playing a game of Operation using a teacher as the bulb-nosed board.

Despite sharing a title and a tagline, this scoop of goop isn’t a remake of the 1995 Clint Howard vehicle. Call this one Children of the Cones — or, if you’re hip to the Brits, Children of the Corneo. Bound to offend more people than it delights, Roth’s exercise in splatstick with sprinkles feels less fully formed than his usual work, perhaps as a self-imposed challenge or an idea he simply needed to knock out of his system. I’m glad he did if that’s the case, although he’s capable of more than this flavor allows. Still, if only all genre throwaways were canny enough to visually reference Alfred Hitchcock’s The Birds and Lucio Fulci’s Zombie, with neither a stretch. —Rod Lott

In theaters Friday, Aug. 7.